When cutting many common glasses to fixed sizes, the starting point as a rule shall be a glass plate of about 6,000×3,210 mm. The raw material is delivered on large A frames and is stored in sets on A or L frames in an uncut plate storage facility. Each glass plate is removed from among the sets at the storage facility by means of a portal crane or by other means and then is transferred to tipping table. By means of vacuum suction devices, said table moves the glass plate from the vertical into the horizontal position.
The glass plate moves from the tipping table onto a cutting table where it is properly positioned and then locked in place. This cutting table is fitted with a usually rotatable cutting head mounted on a two-dimensionally displaceable bridge and able to move in both directions and hence to cut the glass plate at will. The cutting plans, herein agendas, are calculated by a computer using a cut-piece optimizing program and are transferred through a circuit to the machine control device. If required, this device also is able to optimize the cut pieces if required.
Each blank plate initially is roughed out by so-called zero cuts near both transverse and longitudinal edges. Based on these straight reference lines, the cutting agenda predetermined by the cutting optimizing program shall then be carried out along the shortest possible paths by cutting along the x, y and z directions. Additional w-cuts apply to special sizes. Once the glass plate has been fully scribed, it shall be broken up into parts on a sequence of break-off tables.
A first break-off table is used to break off the x-cuts. For that purpose the entire glass plate is tensioned by means of rolls and as a result all the x-cuts will break off during the plate's transit. It is furthermore known to employ a break strip that is forced from below against the glass plate while it is being temporarily stopped. The removal of the sub-plates so made takes place at a higher speed than that of the feed and accordingly the individual plates shall be spaced apart. A second break-off table deflects the glass flow orthogonally and similarly then breaks off the y cuts. Then there is another deviation of the glass flow by 90° in order to break off the Z or W cuts on another table.
When all divisions have been made, all cut pieces are returned by a tipping table into the vertical and are moved to an interim buffer facility. This facility consists of A frames, L frames, compartments carriages and the like which are loaded according to the processing sequence in consecutive manner, for instance regarding a line of insulating glasses.
In order to minimize the space required of such substantially horizontally configured glass cutting facilities and in order to simplify the handling of the glass plates rising vertically both in the storage of the blank plates and also in the interim buffer, the patent document WO A196 22 948 proposed transporting, cutting and breaking all the glass material while it is in its vertical position.
For that purpose a glass table is removed from the blank plate storage and then is directly set up in a cutting table comprising a substantially vertically pointing support surface. A tipping table no longer being required, it may therefore be eliminated. The entire cutting program is then scribed on the cutting table by means of a cut piece optimizing program. Next all cut pieces shall be broken off at consecutive and also vertically configured break-off stations. Essentially the full glass transport shall be contained linearly within one plane. However each sub-plate or each cut piece requires being rotated by 90° in the vertical in order to configure vertically the cutting lines that shall be broken off in the next station. Once the last break off station has been crossed, the finished cut pieces are moved to the interim buffer.
This known glass cutting procedure incurs the substantial drawback that the full volume of one kind of glass must be continuously worked off in relation to the cutting agenda calculated by the cut-piece optimizing program, that is, only after a lot size on the average of 400 m2 of individual glass has been entirely cut to size and without interruption will it be feasible to further process this production lot according to a sequential process. The glass panes that already have been finished are stored in the interim buffer. Illustratively regarding a line of insulating glass, when those already finished cut pieces must be combined with one or more panes of a different glass thickness and/or of different improvements, they must then wait relatively long for further processing, that is until the last kind of glass within the lot has been completely cut up. Such a wait may be as long as half a day and may entail delays in the further processing. The demand for space in the interim buffer is very high.
Another problem is incurred in that at the end of an optimizing run, an often substantially large residual plate shall remain on the cutting table and must be eliminated from the procedure by means of the tipping table or manually, before another kind of glass may be cut. Re-using such a residual plate in a sequential process most of the time is possible only by incurring substantial difficulty because of interference with the optimizing runs. Such conversion or adaptation may entail further delays. Accordingly a glass rupture or a high-speed event occurring in further processing can be cut only outside the conventional logic and hence in much time-delayed manner. The cost in labor is commensurately high, also the manufacturing costs.
As regards a cutting plant disclosed in the patent document DE 42 34 536 A1, the glass plates are moved automatically or manually into a vertically pointing pane support and are positioned via a horizontal transport path relative to a combined cutting, breaking and dividing equipment. Once the glass plate has been stopped, a vertical cut is implemented and the desired sub-plate is then broken off. Said sub-plate next is seized by a manipulator displaceable parallel to the transport path and then is rotated onto its cut edge and deposited in a subsequent temporary storage. If said sub-plate must be divided further, then first the residual plate shall be moved back into the pane support in order to thereafter newly position said sub-plate via the transport path underneath the cutting, breaking and dividing equipment. The part divided off is then seized by the manipulator which deposits it then in the temporary storage. This procedure is repeated until the final cut piece corresponds to the desired size. The temporary storage comprises an outlet which feeds the cut-off panes into subsequent processing. However the cut-off pieces also may be directly deposited into the storage structures of an interim buffer.
Such a procedure is hardly suitable for rationalized mass production. The conversion of the predetermined pane sizes into the required cutting lines does in fact take place by means of a programmed control system. The multiple production of substantially large panels however is just as problematical as the processing of different kinds of glass because the residual pieces always resting on the pane support require either being used according to some priority or being removed individually out of the cutting apparatus, thereby commensurately increasing the cost in time and labor. Therefore a support table always must be completely divided before a change in dimensions or materials may be carried out. The procedure for continuously feeding the manufacture of panes of insulating glass is commensurately unsuitable.